The second issue is that OpenSSL uses PKCS#7 padding to ensure there are full blocks. In this padding scheme, padding is always applied. So, in the case of a full input block, another full block of 0x10 bytes will be added as padding, which means you'll have two blocks of output (which is what you see above).

The -nopad option for openssl enc disables padding (but it will throw an error if your input isn't a multiple of the block size):